1. Field of the Invention
The present invention relates to an RF amplifier, and in particular to a differential RF amplifier.
2. Discussion of the Related Art
Differential RF amplifiers are devices designed to amplify, buffer at unitary gain or attenuate a differential RF input signal. Due to the nature of RF signals, there are various design considerations. For example, generally such circuits are designed with the aim that a common mode voltage between the differential inputs is attenuated, that linearity is high without high current consumption, that little noise is added to the RF signal and that the area of the device is low to keep the cost of the device reasonable.
In practice, known RF amplifiers generally fail to provide good common mode rejection at the same time as acceptable linearity between the input and the output. There is thus a need in the art for a new RF amplifier circuit that is better adapted to meet these design aims.